This is kind of air booster, it keep extra air in the black thing....so when u revv,instead of sucking hard for fresh air.it wil easily get air from there. aftermarket air booster is way too expensive, so DIY is...
hello...
does anyone know of an e8 (non-mr) with the reg xxx 28/23 (i cant remember the letters or the number). its either a light blue or silver car. from what i could see, it was quite stock with just an exhaust...